lithium366 Posted September 30, 2019 Report Share Posted September 30, 2019 Some of you guys remember my dumb questions when I was about to buy my first airplane. Some of you might remember that thanks to your very valuable advices and support I skipped on several suspicious airplanes (they didn't seem suspicious to me without your help). So coincided that short time before I decided that I want to become a proud Mooney owner another baby was born in our family. My wife was turning on Fisher Price piano for the baby every morning with the same song and I was drinking coffee and looking at new ADs on trade-a-plane. Over time I started to look new ads every time I heard the music like a well trained dog and one morning I found it! N9278M that had extremely detailed logs, flown 30-50 hours a year with mid-time engine. It was not a hangar queen in the way that it had some surface paint imperfections and a bit of corrosion but it also had resealed fuel tanks. In other words just like many owners suggest: ignore airplane appearance, look under the skin. And I did. With the help of people on this forum I brought this plane to MSC and did everything I could imagine: Change oil, sent to Blackstone lab, borescope, compressions, checked all ADs and even proceed with an annual later on. Checked gear and opened every panel. Absolutely everyone in that MSC and my instructor were impressed by this bird's technical condition. Blackstone report was ideal as well. One thing I didn't do: I didn't pull a cylinder to look at a camshaft mostly because several A&Ps advised me that this is expensive and seems to be unnecessary taking into an account Blackstone report and the fact that airplane flown quite a bit. Couple weeks back I finished my first oil change at 35h interval and sent oil to Blackstone. I put the old filter aside because I didn't yet had a filter cutter and departed with my friends to Grand Canyon - Vegas weekend trip. Week later I received a Blackstone report with the narrative that they don't understand what changed because both iron and nickel are significantly elevated while previous report was clean. I immediately cut open the filter and found many microscopic shiny dust-like particles that I was able to collect with a magnet. How much? I'd say 1/16 of a teaspoon plus or minus. Not enough to ground an airplane but definitely enough to be concerned. I am on a 10h probation now and really hope it was a one time event. What I don't understand is where nickel can came from in IO-360-A1A? I want to especially stress that I don't blame MSC, previous owner or any members of the forum. In all aspects this bird looked very good at the time of the purchase. P. S: I am still looking trade-a-plane every time I hear that Fisher Price piano. 2 Quote Link to comment Share on other sites More sharing options...
steingar Posted September 30, 2019 Report Share Posted September 30, 2019 I recall no stupid questions. It would suck if a well-treated mistime engine gave up the ghost just as you bought it, but it can happen. Keep an eye on it. Could be a thing, might not. 2 Quote Link to comment Share on other sites More sharing options...
Oldguy Posted September 30, 2019 Report Share Posted September 30, 2019 If anyone here could figure out how to tell when a cam would give up the ghost (or first few layers of metal), we would retire a wealthy individual. It sounds like you have done everything you could to insure a good purchase from doing a pre-buy on the owner and plane to culling through the bad ones until you found one that checked all of the boxes. Let's hope like @steingar says, it is a transient event. But as we all know, feces occurs. Quote Link to comment Share on other sites More sharing options...
lithium366 Posted September 30, 2019 Author Report Share Posted September 30, 2019 21 minutes ago, Oldguy said: If anyone here could figure out how to tell when a cam would give up the ghost (or first few layers of metal), we would retire a wealthy individual. It sounds like you have done everything you could to insure a good purchase from doing a pre-buy on the owner and plane to culling through the bad ones until you found one that checked all of the boxes. Let's hope like @steingar says, it is a transient event. But as we all know, feces occurs. Hope dies last but before pre-buy and before first Blackstone analysis the owner flown this Mooney for 3.5 hours. On old 50 hours oil. And filter was clean. That makes me thing corrosion from some sitting is not a factor 1 Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 30, 2019 Report Share Posted September 30, 2019 50 minutes ago, lithium366 said: Hope dies last but before pre-buy and before first Blackstone analysis the owner flown this Mooney for 3.5 hours. On old 50 hours oil. And filter was clean. That makes me thing corrosion from some sitting is not a factor IIRC, nickel is used in the alloy of the valve guides and maybe some cylinder walls, so it might not automatically be bottom end stuff 1 Quote Link to comment Share on other sites More sharing options...
lithium366 Posted September 30, 2019 Author Report Share Posted September 30, 2019 13 minutes ago, jaylw314 said: IIRC, nickel is used in the alloy of the valve guides and maybe some cylinder walls, so it might not automatically be bottom end stuff How does that top stuff finds it’s way to the filter without damaging cylinder walls and rings? If that’s valve guides I think I should get some symptoms on my engine monitor. Do you know what these symptoms might be? Anyways after 10 hours if I find more metal in the filter I am planning to borescope, check sump screen and if that will not reveal the problem pull one or 2 cylinders Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 30, 2019 Report Share Posted September 30, 2019 18 minutes ago, lithium366 said: How does that top stuff finds it’s way to the filter without damaging cylinder walls and rings? If that’s valve guides I think I should get some symptoms on my engine monitor. Do you know what these symptoms might be? Anyways after 10 hours if I find more metal in the filter I am planning to borescope, check sump screen and if that will not reveal the problem pull one or 2 cylinders There's oil circulating through the area above the valve guides in the rocker arms, I assume that's how any shedding there would make it into the oil sump, not through the cylinder itself... Likewise, if it's from the walls of nickel plated cylinders, that would easily make it to the oil sump. Why not just borescope now? Once the cowling is off and spark plugs are out, it literally takes 10 minutes... 2 Quote Link to comment Share on other sites More sharing options...
lithium366 Posted September 30, 2019 Author Report Share Posted September 30, 2019 3 minutes ago, jaylw314 said: There's oil circulating through the area above the valve guides in the rocker arms, I assume that's how any shedding there would make it into the oil sump, not through the cylinder itself... Likewise, if it's from the walls of nickel plated cylinders, that would easily make it to the oil sump. Why not just borescope now? Once the cowling is off and spark plugs are out, it literally takes 10 minutes... Because if borescope shows nothing I still will need to fly some time before I can check the filter and oil screen for evidence. Also because mechanics are busy. If that’s a valve guide will A&P see the bad one using borescope (I guess, by seeing deposits?) or we will need to pull valve cover? Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 30, 2019 Report Share Posted September 30, 2019 20 minutes ago, lithium366 said: Because if borescope shows nothing I still will need to fly some time before I can check the filter and oil screen for evidence. Also because mechanics are busy. If that’s a valve guide will A&P see the bad one using borescope (I guess, by seeing deposits?) or we will need to pull valve cover? If a valve guide is worn enough, the exhaust valve will not seat well and you might start seeing evidence of valve asymmetry on the cylinder surface (which is the end result you'd be worried about anyway). Otherwise, borescoping won't help visualize the problem directly, though. If you have a nickel-plated cylinder and the debris is from that, you'd see it on the cylinder walls. As to busy mechanics, just ask if they'd be willing to borescope if you undid the cowl and pulled the plugs for them (which you're allowed to do anyway) Quote Link to comment Share on other sites More sharing options...
GLJA Posted September 30, 2019 Report Share Posted September 30, 2019 The Mooney Flyer has a great article in their October issue about metals and what they represent. I'd suggest reading it. Quote Link to comment Share on other sites More sharing options...
DXB Posted September 30, 2019 Report Share Posted September 30, 2019 Ilya, Nickel is usually from a valve guide going bad and coincides with a burnt exhaust valve. A borescope exam of the valve faces should identify the culprit - a tell-tale discolored crescent on one edge will appear. Read https://www.aopa.org/training-and-safety/air-safety-institute/valve-safety. This is essential information that many A&Ps disregard in my experience. The borescope can even catch it before compression drops on a standard compression test, which will also produce an audible hiss at the exhaust. You would need to IRAN or replace that cylinder. The increased Fe in presence of ferrous particles in the filter is more upsetting as it may reflect cam-lifter spalling - I hope not. A broken ring would do it too but you would see a spike in oil consumption also. If you have bad exhaust valves on borescope, might as well pull cylinder(s) soon and look at the cam. 1 Quote Link to comment Share on other sites More sharing options...
jaylw314 Posted September 30, 2019 Report Share Posted September 30, 2019 7 minutes ago, DXB said: Ilya, Nickel is usually from a valve guide going bad and coincides with a burnt exhaust valve. A borescope exam of the valve faces should identify the culprit - a tell-tale discolored crescent on one edge will appear. Read https://www.aopa.org/training-and-safety/air-safety-institute/valve-safety. This is essential information that many A&Ps disregard in my experience. The borescope can even catch it before compression drops on a standard compression test, which will also produce an audible hiss at the exhaust. You would need to IRAN or replace that cylinder. The increased Fe in presence of ferrous particles in the filter is more upsetting as it may reflect cam-lifter spalling - I hope not. A broken ring would do it too but you would see a spike in oil consumption also. If you have bad exhaust valves on borescope, might as well pull cylinder(s) soon and look at the cam. I'll remain hopeful for @lithium366 and hope that the iron is from a valve guide too. At least getting a new cylinder is a (relatively) inexpensive prospect. Unfortunately, I also recall something about crankshaft main bearings having nickel somewhere below the surface layer, but with that I suspect he would have seen a lot more debris and other metals in the oil analysis. You out there @kortopates? Quote Link to comment Share on other sites More sharing options...
DXB Posted October 1, 2019 Report Share Posted October 1, 2019 2 hours ago, lithium366 said: How does that top stuff finds it’s way to the filter without damaging cylinder walls and rings? If that’s valve guides I think I should get some symptoms on my engine monitor. Do you know what these symptoms might be? Anyways after 10 hours if I find more metal in the filter I am planning to borescope, check sump screen and if that will not reveal the problem pull one or 2 cylinders Valve guide wobble only shows up on the monitor when it is advanced and quite dangerous - I have changed 3 cylinders for burnt exhaust valves without the pattern ever appearing. Absence of the pattern provides no assurance at all. The pattern is a rhythmic osciilation in EGT with a periodicity of about 1 minute. The Savvy Analysis website automatically looks for this pattern for free when you upload your data. 1 Quote Link to comment Share on other sites More sharing options...
DXB Posted October 1, 2019 Report Share Posted October 1, 2019 2 hours ago, lithium366 said: Because if borescope shows nothing I still will need to fly some time before I can check the filter and oil screen for evidence. Also because mechanics are busy. If that’s a valve guide will A&P see the bad one using borescope (I guess, by seeing deposits?) or we will need to pull valve cover? Regarding the valve guide, borescope of the exhaust valve face is enough generally to find it (see link provided above). Wobble test with valve cover off can confirm, but generally the two are in agreement. Many A&Ps are resistant to the borescope exam because of inexperience/ignorance. Quote Link to comment Share on other sites More sharing options...
lithium366 Posted October 1, 2019 Author Report Share Posted October 1, 2019 Thank you guys for your support. I just sent particles from a magnet and filter media for a dry analysis. I don’t expect them to give me a part number but who knows... At least that is still cheaper than exploratory surgery. Per your advise I will definitely start with borescope after next oil change and ask A&P to look at valves and walls closely Quote Link to comment Share on other sites More sharing options...
kmyfm20s Posted October 1, 2019 Report Share Posted October 1, 2019 (edited) I wouldn’t be concerned yet, it’s your first oil change with a plane that didn’t fly that much. With all the recent flying of your new plane it probably just loosened up the junk that has collected on the bottom of the oil pan. I would keep flying and see If it continues and develop a pattern. For oil analysis to be correct you need to put the correct amount of makeup oil back in. If you started with 8 quarts at the oil change and took your sample with only 6 quarts remaining you will have high readings. Edited October 1, 2019 by kmyfm20s 1 Quote Link to comment Share on other sites More sharing options...
Yetti Posted October 1, 2019 Report Share Posted October 1, 2019 What year is the cam? What year is the crank? When was the last time the case was split? How many hours on the cylinders? what are the leak down compression numbers? Quote Link to comment Share on other sites More sharing options...
orionflt Posted October 1, 2019 Report Share Posted October 1, 2019 9 hours ago, kmyfm20s said: For oil analysis to be correct you need to put the correct amount of makeup oil back in. If you started with 8 quarts at the oil change and took your sample with only 6 quarts remaining you will have high readings. that statement is incorrect the reason they want to know how much oil was added in between oil changes is so they can correct for the total amount of oil, not to keep it at a fixed amount. if I tried to keep my engine at 8 quarts I would blow 1 quart out every flight, that would skew the data worse and have me thinking i need a new engine because of oil usage. most Lycoming 4 cylinder engines on Mooneys like to sit at 6 quarts, I service to 7 at the oil change and maintain 6. also try not to add oil just before you sample, and sample with the oil hot just after you fly. also let a few oz of oil drain before taking the sample, you want a sample of what is suspended in the oil not what is sitting in the fittings and drain hose. Brian 1 1 Quote Link to comment Share on other sites More sharing options...
kmyfm20s Posted October 1, 2019 Report Share Posted October 1, 2019 2 hours ago, orionflt said: that statement is incorrect the reason they want to know how much oil was added in between oil changes is so they can correct for the total amount of oil, not to keep it at a fixed amount. if I tried to keep my engine at 8 quarts I would blow 1 quart out every flight, that would skew the data worse and have me thinking i need a new engine because of oil usage. most Lycoming 4 cylinder engines on Mooneys like to sit at 6 quarts, I service to 7 at the oil change and maintain 6. also try not to add oil just before you sample, and sample with the oil hot just after you fly. also let a few oz of oil drain before taking the sample, you want a sample of what is suspended in the oil not what is sitting in the fittings and drain hose. Brian By your reasoning which I’m not saying is incorrect it wouldn’t make a difference either way if they take in account the amount of make up oil. The chemistry would go both ways. Quote Link to comment Share on other sites More sharing options...
lithium366 Posted October 1, 2019 Author Report Share Posted October 1, 2019 That is an interesting question... In my understanding oil does not evaporate like water leaving all contaminants in the sump but rather burn (and part of contaminants stay while other is blown via the exhaust) or blown / leak with these contaminants... Quote Link to comment Share on other sites More sharing options...
MrRodgers Posted October 1, 2019 Report Share Posted October 1, 2019 I hope you find the answer to your issue. On another note: I have been flying the airspace over the valley and we have both been on frequency at the same time. I am N9268M in my M20F while you are N9278M. Needless to say there was some added communication going around to make certain we all were where we said we would be. I am based at Van Nuys and I believe you are over at Whiteman. Let's get together sometime. PM me or reach out on Facebook here at the West Coast Mooney Club group page. You can also go to www.westcoastmooneyclub.com and also join the club here on MooneySpace under the CLUB icon on the home page. 2 Quote Link to comment Share on other sites More sharing options...
kmyfm20s Posted October 1, 2019 Report Share Posted October 1, 2019 I didn’t mean to suggest putting a quart in immediately prior to oil sampling but oil time and concentration play a big part in oil samples. Quote Link to comment Share on other sites More sharing options...
orionflt Posted October 1, 2019 Report Share Posted October 1, 2019 14 minutes ago, kmyfm20s said: By your reasoning which I’m not saying is incorrect it wouldn’t make a difference either way if they take in account the amount of make up oil. The chemistry would go both ways. to simplify what I said, you do not need to keep the oil level at 8 quarts if that is where it was serviced to at oil change, but you do need to keep track of how much oil you put in between changes. all engines have a manufactures service level and a minimum operation level for the engine. if you service the engine to the manufactures service level, most engines will blow out a quart or two through the breather on the first one or two flight after service. the remaining level is the optimum oil level for your plane, any more and its all over the belly of your plane. it is also from this level that you can accurately monitor the engine oil consumption. I recommend that you make 1 quart below this point as your service level. IE: if that level is 6 qts, service at 5. 20 minutes ago, lithium366 said: That is an interesting question... In my understanding oil does not evaporate like water leaving all contaminants in the sump but rather burn (and part of contaminants stay while other is blown via the exhaust) or blown / leak with these contaminants... oil does not evaporate, but does burn. the contaminates suspended in the oil will be burnt with the oil. what you need to understand is when an oil analysis is being done, it is reading the contaminants in the sample size not the whole oil system. that sample is a representation of the whole system, by telling them how much oil was added they can compensate for what was burned and what has been diluted with new oil. if you really want to skew an oil sample add a couple qts of fresh oil just before you pull the sample, the clean oil will lower the particle count. It will show in the analysis but will make it difficult to give you accurate reading of the sample. you will usually see a comment or get a question for the annalist stating the condition of the oil doesn't match what was reported. 2 Quote Link to comment Share on other sites More sharing options...
lithium366 Posted October 1, 2019 Author Report Share Posted October 1, 2019 21 minutes ago, orionflt said: to simplify what I said, you do not need to keep the oil level at 8 quarts if that is where it was serviced to at oil change, but you do need to keep track of how much oil you put in between changes. all engines have a manufactures service level and a minimum operation level for the engine. if you service the engine to the manufactures service level, most engines will blow out a quart or two through the breather on the first one or two flight after service. the remaining level is the optimum oil level for your plane, any more and its all over the belly of your plane. it is also from this level that you can accurately monitor the engine oil consumption. I recommend that you make 1 quart below this point as your service level. IE: if that level is 6 qts, service at 5. oil does not evaporate, but does burn. the contaminates suspended in the oil will be burnt with the oil. what you need to understand is when an oil analysis is being done, it is reading the contaminants in the sample size not the whole oil system. that sample is a representation of the whole system, by telling them how much oil was added they can compensate for what was burned and what has been diluted with new oil. if you really want to skew an oil sample add a couple qts of fresh oil just before you pull the sample, the clean oil will lower the particle count. It will show in the analysis but will make it difficult to give you accurate reading of the sample. you will usually see a comment or get a question for the annalist stating the condition of the oil doesn't match what was reported. On my last “bad” oil analysis I started with 8qt of oil replaced at MSC when I purchased an airplane and end up having a sample with 5.5qt in the sump. Added 3qt in between but not right before the sample (so total to make up is 5-6qt for 37.5h tach between oil changes) Blackstone never asked for a sample to be done with the same amount of oil in the sump as what was put during an oil change. Of corse this still doesn’t explain an actual metal in the filter. Quote Link to comment Share on other sites More sharing options...
kmyfm20s Posted October 1, 2019 Report Share Posted October 1, 2019 Yes we need to know the nuances of our individual planes and I probably over simplified my first statement and made it to general. I will change it to if we start and finish with relatively the same oil level with our planes nuances accounted for you will have a better sample. I had a J and would change the oil with 6 quarts because of what you mentioned. I now have an Eagle with and it seems like the consensus seems to be keep it 1 quart over. 1 Quote Link to comment Share on other sites More sharing options...
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